Grazing has become a thing of the past for the majority of U.S. dairy cows. But Justin Morris, Regional Soil Health Specialist with the Natural Resources Conservation Service (NRCS), Madison, Wis, said the availability of even limited pasture acreage could be a tremendous asset to dairies for raising their heifers.
“Year-around confinement is an expensive way to raise replacement heifers,” Morris told the audience at the recent GPS Dairy Summit hosted by GPS Dairy Consulting, LLC. “By grazing heifers for even part of the year, you can grow them more economically into cows that may be better equipped to enter the milking string.”
Morris shared his analysis that grazing heifers for half of the year (May through October) could shave off about one-third of the cost of raising replacement heifers for a year. In his calculations, he estimated the cost of raising 100 heifers in an on-farm confinement system to be about $54,800, compared to $35,500 if those same 100 heifers were grazed for half the year.
That bottom line improves further when one considers the additional revenue from higher first-lactation milk production from heifers raised on partial grazing. Morris cited research indicating grazed heifers produced 1,900 pounds more milk in their first lactation compared to their confinement-raised counterparts. For 100 head of heifers at a $15.00/cwt. milk price, that’s an additional annual gross profit of $28,500.
When grazing systems are managed well, pasture-raised heifers achieve average daily gains (ADG) at or above industry standards. They also have been shown to have greater longevity in the lactating herd, higher fertility rates, and are calmer animals because of frequent human interaction early in their lives.
Why do they do so well? Morris attributes their success to more exercise, less stress on feet and legs, and a diet more conducive to rumen development. He said research from the University of Minnesota showed that, at first calving, heifers on pasture versus confinement had a 50%+ reduction in displaced abomasum (DA), 40% less calving difficulty, and 33% less ketosis.
“Grazed heifers learn to become aggressive eaters on pasture, which transfers to their eating habits at the feed bunk,” Morris shared. “They also have improved physical fitness and fewer leg and hoof problems. Most of them calve with relative ease and enter the lactating herd ready to make milk.”
He cautioned, however, that the process is not as simple as merely turning heifers out onto pasture. To ensure adequate growth and nourishment, pasture should consist of abundant, high-quality forages like the clovers, and a variety of grasses like Meadow fescue, Meadow brome, and Orchardgrass. Soil fertility needs to be monitored closely, and frequent rotation with paddock “resting” periods of 30 to 60 days are essential.
“We call it ‘adaptively managed’ grazing because it is managed daily and adapted to various conditions that can change, like weather, forage growth rates, and animal nutritional needs,” explained Morris. “Continuous or set-stock grazing is not adaptively managed grazing.”
He also advised working with an experienced consultant who can provide management advice – including livestock watering systems – and help with paddock layout configurations. “There is no single way to do it right, but there are definitely ways to do it wrong,” said Morris.